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I am looking for information regarding where the solar hot water transfers into circulating the ammonia through the system and what type of exchanger and if there are any available on the market. I realize I have to chill water and send it back through a coil, at the air handler, but the exchanger unit outside and the ammonia system - I need more education.

Res or not?

I am truly curious whether you want to apply this to a residential air conditioning system. If it is all in the imaginary stage, have you considered imagining a Li-Br system instead of ammonia? The reason I suggest this is that LiBr (I believe) operates at a lower temperature range, something you can generally expect solar collectors to attain.

There has been at least one outlier guy who had a small commercial LiBr system on his home, and he would talk about how that with a solar collector, plus a small amount of gas or oil to heat the system when the sun simply wasn't enough, would be a truly elegant system. I agree but the problem is this elegance exists only in the imaginary world. In the present real world it seems LiBr systems are high maintenance and not really a good fit for a homeowner.

There is another guy who sells a solar powered AC using solar cells and more conventional compression technology. But at maybe 10K for a one ton system, that too is suited only for isolated rich ranchers, and the occasional fanatic.

Arkla air conditioning

In the 80's there were a few systems built that used ammonia absorption cycle machines from an outfit called Arkla. They weren't very successful. LiBr has some potential, and is supposedly being considered for study by NREL.

I remember those Arkla systems being advertised in the Houston area! They burned Natural Gas (NG), and Arkla was a natural gas distribution company which served our area. Apparently these things were hard to service when they broke down, and were heavy users of fuel. When compression-type AC got major efficiency gains in the 1980's and later, it does not seem that any manufacturer was putting in the research to make the Arkla models any better. So whether or not their ammonia cycle design began with a superiority, it lacked the development that greatly improved conventional designs.

When I considered building a house (returned to sanity before done), tried seriously to research NG fueled air conditioning. Found there still were a couple of manufacturers at it, but *all* the scuttlebutt I heard told us the units were 1) expensive, 2) heavy, and 3) hard to service because they are so rare. If I am not mistaken, even in the commercial and industrial arena there is a preference for compression type chillers. Am I right, pros?

This is an interesting idea which IMO is more practical if it stays imaginary. I would cheer on any project to make a modern ammonia (or LiBr) AC that a homeowner can use, but really do not expect it to happen.